Pyridinethione salts are old as shown by U.S. Pat. No. 2,809,971, Oct. 15, 1957 to Bernstein et al. Other patents disclosing similar compounds and processes for making them include U.S. Pat. Nos. 2,786,847, Mar. 26, 1957 to Cislak and 3,583,999, June 8, 1971; 3,590,035, June 29, 1971; and 3,773,770, Nov. 20, 1973 all to Damico.
While the prior art discloses pyridinethione salts and processes for making such salts, it does not suggest forming the salts in an aqueous surfactant medium. Furthermore, there is no suggestion that the crystals formed in such a medium would have superior aesthetic properties and be more compatible in a composition.
It is, therefore, an object of the present invention to provide an improved method for making pyridinethione salt crystals.
It is a further object of the present invention to provide pyridinethione salt crystals which are more compatible in pearlescent cosmetic compositions.
These and other objects will become apparent from the description of the invention which follows.